Removal of the uterine endometrium has proven an excellent alternative to a full hysterectomy in the surgical treatment of abnormal uterine bleeding, a symptom of menorrhagia. A variety of devices and associated techniques for endometrium removal are known. These include transcervical endometrial resection, ablation by laser treatment, ablation by electrosurgery, and thermal or cryogenic cauterization.
One highly successful intrauterine device for cauterization of the endometrium by thermal treatment is disclosed in the commonly owned U.S. Pat. No. 4,949,718 to Neuwirth et al., which is incorporated herein by reference to the extent pertinent. In the device disclosed in that patent, a distendable bladder made of an elastomeric material is mounted at one end portion of a catheter and encloses a heating element. Inserted into the uterus and distended with a liquid, the bladder expands to contact substantially all of the tissue that lines the human uterus, i.e. the uterine endometrium. A source of liquid under pressure, a heat source, and appropriate controls are provided to maintain pressure and temperature at the bladder and endometrium interface to effect necrosis.
Being safe, relatively faster, and less-likely to cause tissue damage to adjacent areas, the device discussed above compares well to the available alternatives. Despite its success, a major concern with such intrauterine devices as with all medical technology is cost. Sterility requirements often dictate that catheters either be fully disposable or in the alternative, durable enough to withstand rigorous thermal and chemical sterilization procedures. Therefore, one must either replace the catheter after each use or pay the extra cost required for highly durable materials as well as sterilization procedures. Until now, this constraint has undesirably contributed to the overall cost of surgical procedures employing intrauterine catheters, and the device discussed above in particular.
Efforts at reducing the overall costs of catheters while maintaining sterility are reflected in the development of disposable sheaths and introducers for reusable catheters. For example, U.S. Pat. No. 4,823,812 to Eshel et al. discloses a reusable rectal catheter for microwave treatment having a disposable jacket of elastomeric material with an integrally formed elastomeric balloon. Such disposable sheaths are ill suited to the intrauterine catheter described above, however, because the sheaths are flexible and subject to failure when used with pressurized fluids.
It would be desirable to provide an improved intrauterine catheter system having a disposable contact portion and a reusable portion substantially insulated from human body contact during use.